diff --git a/lib/bcdice/game_system/DungeonsAndDragons5.rb b/lib/bcdice/game_system/DungeonsAndDragons5.rb
index 9d55e8ada..0d387494b 100644
--- a/lib/bcdice/game_system/DungeonsAndDragons5.rb
+++ b/lib/bcdice/game_system/DungeonsAndDragons5.rb
@@ -14,17 +14,19 @@ class DungeonsAndDragons5 < Base
 
       # ダイスボットの使い方
       HELP_MESSAGE = <<~INFO_MESSAGE_TEXT
-        ・攻撃ロール　AT[x][@c][>=t][y]
+        ・攻撃ロール　AT[x][@c][>=t][y][B]
         　x：+-修正。省略可。
         　c:クリティカル値。省略可。
         　t:敵のアーマークラス。>=を含めて省略可。
         　y:有利(A), 不利(D)。省略可。
+        　B:(B)ブレスやガイダンスによる+1d4。省略可。
         　ファンブル／失敗／成功／クリティカル を自動判定。
         　例）AT AT>=10 AT+5>=18 AT-3>=16 ATA AT>=10A AT+3>=18A AT-3>=16 ATD AT>=10D AT+5>=18D AT-5>=16D
-        　    AT@19 AT+5@18 AT-2@19>=15
-        ・能力値判定　AR[x][>=t][y]
+        　    AT@19 AT+5@18 AT-2@19>=15 AT+3>=18AB AT+3>=18DB
+        ・能力値判定　AR[x][>=t][y][b]
         　攻撃ロールと同様。失敗／成功を自動判定。
         　例）AR AR>=10 AR+5>=18 AR-3>=16 ARA AR>=10A AR+3>=18A AR-3>=16 ARD AR>=10D AR+5>=18D AR-5>=16D
+        　     AR+3>=18AB AR+3>=18DB
         ・両手持ちのダメージ　2HnDx[m]
         　n:ダイスの個数
         　x:ダイスの面数
@@ -33,7 +35,7 @@ class DungeonsAndDragons5 < Base
         　例)2H3D6 2H1D10+3 2H2D8-1
       INFO_MESSAGE_TEXT
 
-      register_prefix('AT([+-]\d+)?(@\d+)?(>=\d+)?[AD]?', 'AR([+-]\d+)?(>=\d+)?[AD]?', '2H(\d+)D(\d+)([+-]\d+)?')
+      register_prefix('AT', 'AR', '2H')
 
       def initialize(command)
         super(command)
@@ -57,17 +59,27 @@ def number_with_sign_from_int(number)
 
       # 攻撃ロール
       def attack_roll(command)
-        m = /^AT([-+]\d+)?(@(\d+))?(>=(\d+))?([AD]?)/.match(command)
+        m = /^AT([-+\d]+)?(@(\d+))?(>=(\d+))?([AD]?)6?(B?)/.match(command)
         unless m
           return nil
         end
 
-        modify = m[1].to_i
+        if m[1]
+          if Arithmetic.eval(m[1], @round_type)
+            modify = Arithmetic.eval(m[1], @round_type)
+          else
+            return nil
+          end
+        else
+          modify = 0
+        end
         critical_no = m[3].to_i
         difficulty = m[5].to_i
         advantage = m[6]
+        bonus = m[7]
 
         usedie = 0
+        bonus_mod = 0
         roll_die = ""
 
         dice_command = "AT#{number_with_sign_from_int(modify)}"
@@ -82,6 +94,9 @@ def attack_roll(command)
         unless advantage.empty?
           dice_command += advantage.to_s
         end
+        if bonus == "B"
+          dice_command += bonus.to_s
+        end
 
         output = ["(#{dice_command})"]
 
@@ -98,14 +113,28 @@ def attack_roll(command)
           end
         end
 
+        if bonus == "B"
+          bonus_mod = @randomizer.roll_once(4).to_i
+        end
+
         if modify != 0
-          output.push("#{roll_die}#{number_with_sign_from_int(modify)}")
-          output.push((usedie + modify).to_s)
+          if bonus_mod != 0
+            output.push("#{roll_die}#{number_with_sign_from_int(modify)}#{number_with_sign_from_int(bonus_mod)}")
+            output.push((usedie + modify + bonus_mod).to_s)
+          else
+            output.push("#{roll_die}#{number_with_sign_from_int(modify)}")
+            output.push((usedie + modify).to_s)
+          end
         else
-          unless advantage.empty?
-            output.push(roll_die)
+          if bonus_mod != 0
+            output.push("#{roll_die}#{number_with_sign_from_int(bonus_mod)}")
+            output.push((usedie + bonus_mod).to_s)
+          else
+            unless advantage.empty?
+              output.push(roll_die)
+            end
+            output.push(usedie.to_s)
           end
-          output.push(usedie.to_s)
         end
 
         result = Result.new
@@ -117,7 +146,7 @@ def attack_roll(command)
           result.fumble = true
           output.push(translate('fumble'))
         elsif difficulty > 0
-          if usedie + modify >= difficulty
+          if usedie + modify + bonus_mod >= difficulty
             result.success = true
             output.push(translate('success'))
           else
@@ -139,16 +168,18 @@ def attack_roll(command)
 
       # 能力値ロール
       def ability_roll(command)
-        m = /^AR([-+]\d+)?(>=(\d+))?([AD]?)/.match(command)
+        m = /^AR([-+\d]+)?(>=(\d+))?([AD]?)(B?)/.match(command)
         unless m
           return nil
         end
 
-        modify = m[1].to_i
+        modify = m[1] ? Arithmetic.eval(m[1], @round_type) : 0
         difficulty = m[3].to_i
         advantage = m[4]
+        bonus = m[5]
 
         usedie = 0
+        bonus_mod = 0
         roll_die = ""
 
         dice_command = "AR#{number_with_sign_from_int(modify)}"
@@ -158,6 +189,9 @@ def ability_roll(command)
         unless advantage.empty?
           dice_command += advantage.to_s
         end
+        if bonus == "B"
+          dice_command += bonus.to_s
+        end
 
         output = ["(#{dice_command})"]
 
@@ -174,19 +208,33 @@ def ability_roll(command)
           end
         end
 
+        if bonus == "B"
+          bonus_mod = @randomizer.roll_once(4).to_i
+        end
+
         if modify != 0
-          output.push("#{roll_die}#{number_with_sign_from_int(modify)}")
-          output.push((usedie + modify).to_s)
+          if bonus_mod != 0
+            output.push("#{roll_die}#{number_with_sign_from_int(modify)}#{number_with_sign_from_int(bonus_mod)}")
+            output.push((usedie + modify + bonus_mod).to_s)
+          else
+            output.push("#{roll_die}#{number_with_sign_from_int(modify)}")
+            output.push((usedie + modify).to_s)
+          end
         else
-          unless advantage.empty?
-            output.push(roll_die)
+          if bonus_mod != 0
+            output.push("#{roll_die}#{number_with_sign_from_int(bonus_mod)}")
+            output.push((usedie + bonus_mod).to_s)
+          else
+            unless advantage.empty?
+              output.push(roll_die)
+            end
+            output.push(usedie.to_s)
           end
-          output.push(usedie.to_s)
         end
 
         result = Result.new
         if difficulty > 0
-          if usedie + modify >= difficulty
+          if usedie + modify + bonus_mod >= difficulty
             result.success = true
             output.push(translate('success'))
           else
@@ -208,14 +256,14 @@ def ability_roll(command)
 
       # 武器の両手持ちダメージ
       def twohands_damage_roll(command)
-        m = /^2H(\d+)D(\d+)([+-]\d+)?/.match(command)
+        m = /^2H(\d+)D(\d+)([-+\d]+)?/.match(command)
         unless m
           return nil
         end
 
         dice_count = m[1].to_i
         dice_number = m[2].to_i
-        modify = m[3].to_i
+        modify = m[3] ? Arithmetic.eval(m[3], @round_type) : 0
         mod_str = number_with_sign_from_int(modify)
         output = ["(2H#{dice_count}D#{dice_number}#{mod_str})"]
 
diff --git a/test/data/DungeonsAndDragons5.toml b/test/data/DungeonsAndDragons5.toml
index faf766bc3..52335483a 100644
--- a/test/data/DungeonsAndDragons5.toml
+++ b/test/data/DungeonsAndDragons5.toml
@@ -56,6 +56,13 @@ rands = [
   { sides = 20, value = 1 },
 ]
 
+[[ test ]]
+game_system = "DungeonsAndDragons5"
+input = "AT+ 加減算記号のみで数字のない不正入力時の処理確認"
+output = ""
+rands = [
+]
+
 
 [[ test ]]
 game_system = "DungeonsAndDragons5"
@@ -175,6 +182,24 @@ rands = [
   { sides = 20, value = 19 },
 ]
 
+[[ test ]]
+game_system = "DungeonsAndDragons5"
+input = "AT+2+3>=10 加減算修正の表示確認"
+output = "(AT+5>=10) ＞ 19+5 ＞ 24 ＞ 成功"
+success = true
+rands = [
+  { sides = 20, value = 19 },
+]
+
+[[ test ]]
+game_system = "DungeonsAndDragons5"
+input = "AT+7-2>=10 加減算修正の表示確認"
+output = "(AT+5>=10) ＞ 19+5 ＞ 24 ＞ 成功"
+success = true
+rands = [
+  { sides = 20, value = 19 },
+]
+
 [[ test ]]
 game_system = "DungeonsAndDragons5"
 input = "AT+3>=10 クリティカルの表示確認"
@@ -296,6 +321,47 @@ rands = [
 ]
 
 
+[[ test ]]
+game_system = "DungeonsAndDragons5"
+input = "ATB ボーナスの表示確認"
+output = "(ATB) ＞ 2+3 ＞ 5"
+rands = [
+  { sides = 20, value = 2 },
+  { sides = 4, value = 3 },
+]
+
+[[ test ]]
+game_system = "DungeonsAndDragons5"
+input = "AT+3>=18B ボーナスの表示確認"
+output = "(AT+3>=18B) ＞ 2+3+3 ＞ 8 ＞ 失敗"
+failure = true
+rands = [
+  { sides = 20, value = 2 },
+  { sides = 4, value = 3 },
+]
+
+[[ test ]]
+game_system = "DungeonsAndDragons5"
+input = "AT-3>=14B"
+output = "(AT-3>=14B) ＞ 18-3+3 ＞ 18 ＞ 成功"
+success = true
+rands = [
+  { sides = 20, value = 18 },
+  { sides = 4, value = 3 },
+]
+
+[[ test ]]
+game_system = "DungeonsAndDragons5"
+input = "AT-3>=15DB"
+output = "(AT-3>=15DB) ＞ [18,3]-3+3 ＞ 3 ＞ 失敗"
+failure = true
+rands = [
+  { sides = 20, value = 18 },
+  { sides = 20, value = 3 },
+  { sides = 4, value = 3 },
+]
+
+
 [[ test ]]
 game_system = "DungeonsAndDragons5"
 input = "AR コマンドのみの表示確認"
@@ -407,6 +473,24 @@ rands = [
   { sides = 20, value = 19 },
 ]
 
+[[ test ]]
+game_system = "DungeonsAndDragons5"
+input = "AR+2+3>=10 加減算修正の表示確認"
+output = "(AR+5>=10) ＞ 19+5 ＞ 24 ＞ 成功"
+success = true
+rands = [
+  { sides = 20, value = 19 },
+]
+
+[[ test ]]
+game_system = "DungeonsAndDragons5"
+input = "AR+5-10>=10 加減算修正の表示確認"
+output = "(AR-5>=10) ＞ 19-5 ＞ 14 ＞ 成功"
+success = true
+rands = [
+  { sides = 20, value = 19 },
+]
+
 [[ test ]]
 game_system = "DungeonsAndDragons5"
 input = "ARA 有利の表示確認"
@@ -467,6 +551,36 @@ rands = [
 ]
 
 
+[[ test ]]
+game_system = "DungeonsAndDragons5"
+input = "ARB ボーナスの表示確認"
+output = "(ARB) ＞ 3+3 ＞ 6"
+rands = [
+  { sides = 20, value = 3 },
+  { sides = 4, value = 3 },
+]
+
+[[ test ]]
+game_system = "DungeonsAndDragons5"
+input = "AR>=10B 失敗の表示確認"
+output = "(AR>=10B) ＞ 3+3 ＞ 6 ＞ 失敗"
+failure = true
+rands = [
+  { sides = 20, value = 3 },
+  { sides = 4, value = 3 },
+]
+
+[[ test ]]
+game_system = "DungeonsAndDragons5"
+input = "AR>=10B 成功の表示確認"
+output = "(AR>=10B) ＞ 19+3 ＞ 22 ＞ 成功"
+success = true
+rands = [
+  { sides = 20, value = 19 },
+  { sides = 4, value = 3 },
+]
+
+
 [[ test ]]
 game_system = "DungeonsAndDragons5"
 input = "2H3D6 両手持ちダメージ、振り直しなし、修正なし"
@@ -497,6 +611,26 @@ rands = [
   { sides = 6, value = 3 },
 ]
 
+[[ test ]]
+game_system = "DungeonsAndDragons5"
+input = "2H3D6+1+2 振り直しなし、加減算修正"
+output = "(2H3D6+3) ＞ [3,4,5]+3 ＞ 15"
+rands = [
+  { sides = 6, value = 3 },
+  { sides = 6, value = 4 },
+  { sides = 6, value = 5 },
+]
+
+[[ test ]]
+game_system = "DungeonsAndDragons5"
+input = "2H3D6-10+5 振り直しなし、加減算修正"
+output = "(2H3D6-5) ＞ [5,4,3]-5 ＞ 7"
+rands = [
+  { sides = 6, value = 5 },
+  { sides = 6, value = 4 },
+  { sides = 6, value = 3 },
+]
+
 [[ test ]]
 game_system = "DungeonsAndDragons5"
 input = "2H3D6 振り直しあり、修正なし"